LymphoStat-B™

MedImmune Cambridge-derived Clinical Development
Partners	Product	Target	Disease	PreC	PhI	PhII	PhIII	Fld	Mkt
HGSI	LymphoStat-B™	BLyS	systemic lupus erythematosus
HGSI	LymphoStat-B™	BLyS	rheumatoid arthritis

Key to table

LymphoStat-B™ (belimumab) is a human anti-BLyS monoclonal antibody being developed to treat systemic lupus erythematosus and rheumatoid arthritis. LymphoStat-B was isolated and optimised by CAT in collaboration with HGSI, with HGSI responsible for its further development and marketing under the terms of an exclusive product licence granted by CAT in 2002.

LymphoStat-B is a human monoclonal antibody that specifically recognises and inhibits the biological activity of BlyS or B-Lymphocyte Stimulator. BLyS is a naturally occurring protein that is required for the development of B-lymphocyte cells into mature plasma B cells. In systemic lupus erythematosus and rheumatoid arthritis and certain other autoimmune diseases, elevated levels of BLyS are believed to contribute to the production of autoantibodies - antibodies that attack and destroy the body's own healthy tissues.

In April 2005, HGSI announced that LymphoStat-B met the primary efficacy and safety endpoints in its Phase II trial for rheumatoid arthritis. LymphoStat-B was shown to be safe and well tolerated, biologically active and to reduce the signs and symptoms of rheumatoid arthritis.

LymphoStat-B is currently in Phase III development for systemic lupus erythematosus. In February 2007, one of two Phase III, double blind, placebo-controlled trials was initiated. The second trial commenced in May 2007. Both will evaluate the efficacy and safety of LymphoStat-B in SLE and will run for 76 weeks and 52 weeks, respectively. It is planned that 810 patients will be enrolled in each of the two studies.

Prelimnary data from the Phase III study in patients with SLE is expected to be published in 2009

In July 2005, HGSI announced that GlaxoSmithKline exercised its option to develop and commercialise LymphoStat-B jointly with HGSI. GlaxoSmithKline and HGSI will share equally in the Phase III and Phase IV development costs of LymphoStat-B, as well as sales and marketing expenses and profits of a commercialised product, under a co-development and co-promotion agreement.